Aqueous emulsions of amine-functionalized organopolysiloxanes

ABSTRACT

Aqueous emulsions of amine functionalized organopolysiloxane particles useful in personal care applications and methods for making are described. Useful compositions can be made by contacting at elevated temperatures, aqueous emulsions of organopolysiloxane particles having a volume average particle diameter in a range between about 300 nanometers and about 1 micron with an amine functionalized organosilicon source material, such as an aminoorganopolyalkoxysilane or an aminoorganopoly(diorganosiloxane) fluid.

BACKGROUND OF THE INVENTION

[0001] The present invention is directed to stable anionic aqueousemulsions of organopolysiloxane particles having a volume averageparticle diameter (Dv) of at least about 300 nanometers (nm) andconsisting essentially of chemically combined aminoorganosiloxyfunctional units and diorganosiloxy units. More particularly, thepresent invention is directed to a method involving the reaction of anaqueous acid catalyzed emulsion of organopolysiloxane particles with anamine functional organosilicon material.

[0002] There is shown in U.S. Pat. No. 5,726,270, 5,856,402, and5,900,460 to Craig, semi-continuous methods for making acid catalyzedaqueous dispersions of organopolysiloxanes useful in coatingapplications, including personal care. For example, in the formulationof a silicone-containing hair shampoo, experience has shown thatdesirable results can be achieved with aqueous dispersions oforganopolysiloxane particles having a volume average particle diameterin the range of at least about 300 nanometers to about 1 micron. It hasbeen found that improvements in hair styling with silicone-containingshampoos can be achieved in particular situations as a result of the“smoothing out” effect. It is speculated that silicones in the form ofaqueous dispersions of organopolysiloxane particles having an averagediameter of at least about 300 nanometers can more readily coat thesurface of the hair shaft.

[0003] Experience also has shown that further benefits in coating and inpersonal care applications can be obtained with aqueous dispersions oforganopolysiloxane particles if the dispersed particles are modifiedwith a functional group, such as aminoorgano, epoxy, carboxy, ormercapto. However, previous efforts to functionalize suchorganopolysiloxane particles during their initial formation from cyclicpoly(diorganosiloxane) under semi-continuous conditions, often resultedin functionalized organopolysiloxane particles with a volume averageparticle diameter less than about 300 nanometers. In particular,although an aqueous emulsion of organopolysiloxane particles having avolume average particle diameter of at least about 300 nanometers can begenerated under semi-continuous conditions by the acid catalyzedequilibration of cyclic poly(diorganosiloxane) in the absence of theamine functionalized organosilicon source material, efforts tofunctionalize the particles during the initial particle formation undersemi-continuous conditions in the presence of an amine functionalizedorganosilicon source material typically results in particles having avolume average particle diameter less than about 300 nanometers.

[0004] Further, a procedure for making an acid catalyzed aqueousdispersion of organopolysiloxane particles with aminoorgano functionalgroups involves working with competing anionic and cationic charges. Inaddition to adversely affecting particle size, amine functionalizationefforts also can impact adversely on emulsion stability andacid-catalyzed polymerization rates. In particular, emulsion instabilityis favored as a result of the presence of aminoorgano functional groups,and anionic silicone emulsion particles as shown by U.S. Pat. No.5,045,576. A satisfactory method is therefor needed to make stableaqueous emulsions of amine functionalized organopolysiloxane particleshaving a volume average particle diameter of at least about 300nanometers using an acid catalyzed process.

BRIEF SUMMARY OF THE INVENTION

[0005] In one embodiment, the present invention is an aqueous emulsionof amine functionalized organopolysiloxane particles useful in personalcare applications, and having a volume average particle diameter of atleast about 300 nanometers.

[0006] In another embodiment, the present invention is a substantiallystable aqueous emulsion having in a range between about 5% by weight andabout 60% by weight solids, comprising amine functionalizedorganopolysiloxane particles having a volume average particle diameterof at least about 300 nanometers, said particles consisting essentiallyof in a range between about 50 mole % and about 99 mole % ofdiorganosiloxy units, chemically combined with in a range between about50 mole % and about 1 mole % of (aminoorgano)organosiloxy units.

[0007] In still another embodiment, the present invention is a methodfor making an aqueous emulsion of amine functionalizedorganopolysiloxane particles useful in personal care applications, andhaving a total solids content in a range between about 5% by weight andabout 60% by weight, comprising effecting reaction at a temperature in arange between about 25° C. and about 110° C., and in the presence of aneffective amount of an acid catalyst surfactant, between (A) an aqueousemulsion of organopolysiloxane particles having a volume averageparticle diameter of at least about 300 nanometers, and (B) an aminefunctionalized organosilicon source material, wherein there is used in arange between about 1 part and about 50 parts by weight of (B) per 100parts of (A).

[0008] In still another embodiment, the present invention is a methodfor making a substantially stable aqueous emulsion having in a rangebetween about 5% by weight and about 60% by weight of solids, andcomprising amine functionalized organopolysiloxane particles having avolume average particle diameter of at least about 300 nanometers,comprising the steps of:

[0009] (1) providing an aqueous emulsion comprising in a range betweenabout 1% by weight and about 50% by weight organopolysiloxane particleshaving a volume average particle diameter of at least about 300nanometers, by either,

[0010] (a) equilibrating under semi-continuous conditions at atemperature in a range between about 25° C. and about 110° C., anaqueous mixture comprising cyclic poly(diorganosiloxane) and aneffective amount of an acid catalyst surfactant to form an aqueousemulsion of organopolysiloxane particles having a volume averageparticle diameter of at least about 300 nanometers, or

[0011] (b) employing an aqueous emulsion of preformed organopolysiloxaneemulsion seeds having a volume average particle diameter of at leastabout 300 nanometers; and

[0012] (2) effecting reaction between the organopolysiloxane particlesor seeds in the aqueous emulsion of (1), and an amine functionalizedorganosilicon source material in a range between about 1 part and about50 parts by weight per 100 parts of such organopolysiloxane particles orseeds.

DETAILED DESCRIPTION OF THE INVENTION

[0013] Within the context of the present invention “substantially stableaqueous emulsion” means an emulsion in which the dispersed particles donot appreciably agglomerate during the typical shelf-life of theemulsion. In one of its embodiments “semi-continuous” refers to aprocess for functionalizing organopolysiloxane particles which employsorganopolysiloxane particle seeds prepared in a separate step. In otherembodiments, “semi-continuous” refers to a reaction which does not needto be stopped in order to add more reactants.

[0014] The present invention is based on the discovery that effectiveaminoorgano functionalization of dispersed organopolysiloxane particleshaving a volume average particle diameter of at least about 300nanometers can be achieved by direct treatment of an acid catalyzedaqueous dispersion of said particles with an amine functionalizedorganosilicon source material in the form of an aminoorganofunctionalized organosilicon member selected from the group consistingof an alkoxysilane, a cyclic poly(diorganosiloxane), and apoly(diorganosiloxane) fluid. Surprisingly, the volume average particlediameter of the resulting aminoorgano functionalized particles is foundto be substantially the same as the volume average particle diameter ofthe starting unfunctionalized organopolysiloxane particles.

[0015] In one embodiment, a substantially stable aqueous emulsion offunctionalized organopolysiloxane particles with the desired size rangeis produced by a two-staged, acid-catalyzedsemi-continuous/semi-continuous or semi-continuous/batch process wherebythe particle size is substantially maintained from the first stage andfunctionalization occurs in a second stage through equilibration intothe particles of an amine functionalized organosilicon source material,particularly an aminoorgano functionalized alkoxy silane, cyclicpoly(diorganosiloxane), or poly(diorganosiloxane) fluid. “Substantiallymaintained” as used herein refers to a volume average particle size oforganopolysiloxane particles which changes less than about 50%,preferably less than about 20%, and most preferably less than about 10%.Often, a semi-continuous process is utilized in the first stage wherein,for example, a cyclic poly(diorganosiloxane), acid catalyst surfactant,and water are added to a preheated reactor, either as separate feeds orin various combinations with each other, or as a pre-emulsified mixturecontaining water and optionally additional surfactant over somespecified time period. The reaction mixture may be heated for a periodof time after addition of precursor to ensure formation oforganopolysiloxane particles in the desired size range. Upon completionof the first stage, the reaction mixture may be cooled to any desiredtemperature, for example to about room temperature, or maintained atreaction temperature. The amine functionalized organosilicon sourcematerial may be added, either semi-continuously or batchwise, at whichpoint the reactor may be heated to a desired reaction temperature orsimply maintained at a desired reaction temperature for a period of timeto ensure equilibration of functionalized species into the particles.The length of time between stages may be of any convenient durationprovided a particle size in the desired range is substantially achievedin the first stage and adequate functionality incorporation is achievedin the second stage.

[0016] In another embodiment, a substantially stable aqueous emulsion offunctionalized organopolysiloxane particles with the desired size rangeis produced by post-functionalization of a pre-existing, pre-synthesizedorganopolysiloxane emulsion comprising particles with volume averageparticle diameter of at least about 300 nanometers.Post-functionalization using amine functionalized organosilicon sourcematerial may be performed essentially as described above. The synthesisof the preexisting emulsion can occur at any point prior to thefunctionalization step, including a separate emulsion manufacturingstep.

[0017] Aqueous emulsions of organopolysiloxane particles used in thepractice of the present invention can be employed as preformedorganopolysiloxane particles or “seeds”. Said particles typically have avolume average particle diameter (Dv) of at least about 300 nanometers,and preferably in a range between about 300 nanometers and about 1micron. Alternatively, the initial volume average diameter of saidparticles may be less than about 300 nanometers and is increased togreater than about 300 nanometers before functionalization, for examplethrough equilibration with cyclic poly(diorganosiloxane) in the presenceof catalyst.

[0018] Another source of the organopolysiloxane particles is by theequilibration of at least one cyclic poly(diorganosiloxane).Accordingly, an aqueous mixture having in a range between about 5% byweight and about 60% by weight of cyclic poly(diorganosiloxane) can beagitated and equilibrated in the presence of an acid catalyst surfactantat temperatures in a range between about 25° C. and about 110° C.Equilibration of the cyclic poly(diorganosiloxane) can be conducted in asemi-continuous manner to form particles comprisingpoly(diorganosiloxane) structural units and having a volume averageparticle diameter of at least about 300 nanometers, and preferably in arange between about 300 nanometers and about 1 micron.

[0019] Cyclic (polydiorganosiloxane)s included in the practice of theinvention, are for example, one or more members selected from a C₃₋₈cyclic diorganosiloxane, and most preferably a C₃₋₄ cyclicpoly(dimethylsiloxane), such as hexamethyltrisiloxane andoctamethylcyclotetrasiloxane, or “tetramer”. However, other C₁₋₆ organoradicals can be present in addition to or in place of methyl, such asethyl, propyl, butyl and phenyl.

[0020] Acid catalyst surfactants include, for example, surface-activesulfonic acids, which can be substituted with alkyl, alkaryl, or arylradicals. Examples of mixtures of surface-active sulfonic acid saltswith strong mineral acids, and combinations thereof are disclosed inU.S. Pat. No. 3,294,725, also can be used. A particularly preferred acidcatalyst surfactant is dodecylbenzenesulfonic acid. An effective amountof the acid catalyst surfactant is in a range between about 0.25% byweight and about 5% by weight of acid catalyst surfactant based on theweight of cyclic poly(diorganosiloxane) initially present in the aqueousmixture. Preferred weight ratios of cyclic poly(diorganosiloxane) toacid catalyst surfactant to water can vary in a range between about70:1:29 and about 75:5:20.

[0021] Among the amine functionalized organosilicon source materialswhich can be used in the practice of the invention, there are includedaminoorganopolyalkoxysilanes, such as gamma-aminopropyltrimethoxysilaneand gamma-aminopropyltriethoxysilane.

[0022] Aminoorgano-substituted organopolysiloxanes, such as aminefunctionalized poly(diorganosiloxane) fluids, also can be used as aminefunctionalized organosilicon source materials. These amine sourcematerials can have a viscosity in a range between about 100 centipoiseand about 100,000 centipoise at 25° C., and consist essentially ofchemically combined aminoalkylorganosiloxy units and diorganosiloxyunits, wherein there can be present in a range between about 1 mole %and about 99 mole % of aminoalkylorganosiloxy units, such asaminopropylmethylsiloxy units, based on the total moles ofaminoalkylorganosiloxy units and diorganosiloxy units, such asdimethylsiloxy units.

[0023] The amount of amine functionalized organosilicon source materialused to functionalize organopolysiloxane particles is by weight in arange between about 1 part and about 50 parts, and preferably in a rangebetween about 1 and about 10 parts, per 100 parts of organopolysiloxaneparticles. Reaction between organopolysiloxane particles and aminefunctionalized organosilicon source materials can be effected attemperatures in a range between about 25° C. and about 110° C. Dependingupon such factors as the identity of the source material, it may bepreferred to add the amine functionalized organosilicon source materialto existing organopolysiloxane particles at temperatures in a rangebetween about room temperature and about 90° C., and preferably attemperatures in a range between about room temperature and about 40° C.followed by heating the resulting aqueous mixture to minimize prematurehydrolysis of alkoxysilicon groups which may result in unwanted coagulum(heterogeneous polysiloxane product) and lower product yield. The finalproduct emulsion typically has in a range between about 5% by weight andabout 60% by weight and preferably in a range between about 30% byweight and about 60% by weight solids level.

[0024] In order that those skilled in the art will be better able topractice the present invention, the following examples are given by wayof illustration, and not by way of limitation. In these examples, allparts which are referenced are by weight unless otherwise indicated.

EXAMPLE 1

[0025] An aqueous emulsion of poly(dimethylsiloxane) seeds was preparedby initially heating to 85° C. under continuous agitation for 125minutes, a mixture of 166 grams of water and 48 grams of apre-emulsified mixture. The pre-emulsified mixture consisted of 298grams of octamethylcyclotetrasiloxane, 4.5 grams ofdodecylbenzenesulfonic acid, and 110 grams of water. The remainder ofthe pre-emulsified mixture was then added over 85 minutes. The mixturewas maintained at 85° C. for an additional 90 minutes, then cooled toroom temperature. Based on method of preparation and the employment of aNicomp 370 Submicron Particle Sizer instrument, applying a Gaussiananalysis protocol, there was obtained an aqueous emulsion ofpoly(dimethylsiloxane) particles having volume average particle diameterof 431 nanometers.

[0026] There was added to the above aqueous emulsion with stirring 4.8grams of SF1708 (a product of GE Silicones, Waterford, N.Y.), which is atrimethylsiloxy-terminated, amino-substituted methylpolysiloxane fluidconsisting essentially of dimethylsiloxy units and(aminopropyl)methylsiloxy units having a viscosity of 2000 centipoise at25° C., and an amine content of about 0.8 milliequivalents base pergram. The resulting mixture was heated to 85° C. and maintained at thattemperature for 270 minutes. The mixture was then cooled to roomtemperature. Based on method of preparation, and infrared (IR) spectralanalysis, there was obtained an aqueous emulsion of aminopropylfunctionalized poly(dimethylsiloxane) particles.

[0027] Utilizing a CEM Labwave 9000 gravimetric microwave drier with 20minute heat times and at full microwave output, the emulsion was foundto have 45.4% total solids by weight. The volume average particlediameter of the particles in the amino functionalizedpoly(dimethylsiloxane) emulsion was found to be substantially unchangedas compared to the original aqueous emulsion free of aminofunctionalization. The amino functionalized poly(dimethylsiloxane)emulsion was found to be stable and compatible with other anionicmaterials, and can be used in applications such as coatings and personalcare.

Control Example 1

[0028] The following control example shows that when the aminefunctionalized organosilicon source material is introduced into thereaction mixture either prior to or during the initial formation of theaqueous emulsion of polymerized organopolysiloxane seeds, an aminofunctionalized poly(dimethylsiloxane) emulsion may result which hasvolume average particle diameter less than about 300 nanometers.

[0029] A mixture of 100 grams of water, 3.2 grams ofdodecylbenzenesulfonic acid, 321 grams of octamethylcyclotetrasiloxane,and 4.8 grams of SF1708 was added to a reactor containing 150 grams ofwater at 86° C. over a period of 310 minutes. The mixture was dilutedwith 200 grams of water to lower the reaction mixture viscosity, andthen maintained for an additional five hours at 86° C., and cooled toroom temperature. There was obtained an emulsion ofpoly(dimethylsiloxane)-containing particles having a volume averageparticle diameter of 121 nanometers and a total solids level of 38% byweight.

EXAMPLE 2

[0030] While 150 grams of water at 86° C. was being agitated in areactor, there was added over a period of 345 minutes a pre-emulsifiedmixture of 100 grams of water, 3.2 grams of dodecylbenzenesulfonic acid,and 319 grams of octamethylcyclotetrasiloxane. After completion of theemulsion addition, the resulting reaction mixture was heated for anadditional 30 minutes and then cooled rapidly. Based on method ofpreparation, there was obtained an aqueous emulsion ofpoly(dimethylsiloxane) seeds having a volume average particle diameterof 935 nm.

[0031] The above emulsion was then heated to 38° C., and 4.2 grams ofaminosilicone fluid SF1708 was thereafter added batchwise with stirring.The resulting mixture was then heated to 86° C. and maintained at thattemperature for 6 hours and cooled to ambient temperature. Based onmethod of preparation and use of analytical procedures shown in Example1, there was obtained an aqueous emulsion having 48.1% by weight totalsolids, of amine functionalized organopolysiloxane particles havingvolume average particle diameter of 953 nanometers. The siliconeemulsion was also free of coagulum, and stable and compatible with otheranionic materials; it can be used in applications such as coatings andpersonal care.

EXAMPLE 3

[0032] There was added batch-wise with constant stirring at 22° C. anaqueous mixture of 9.2 grams of gamma-aminopropyltriethoxysilane and19.1 grams of dodecylbenzenesulfonic acid to 620 grams of a preformedpoly(dimethylsiloxane) emulsion having a total weight % solids of 50.7,and a volume average particle diameter of 731 nanometers. The resultingreaction mixture was heated to 50° C. for 2.5 hours and cooled to roomtemperature. Based on method of preparation and analytical proceduresshown in example 1, there was obtained an aqueous emulsion of aminefunctionalized organopolysiloxane particles having a volume averageparticle diameter of 803 nanometers and a total weight % solids of51.4%. The aqueous emulsion of amine functionalized organopolysiloxaneparticles is useful in personal care applications.

EXAMPLE 4

[0033] A mixture of 300 grams of a preexisting poly(dimethylsiloxane)emulsion (45% solids level; volume average particle diameter of 156nanometers) was agitated and heated at 85° C. There was added to thereactor over 195 minutes a pre-emulsified mixture of 210 gramsoctamethylcyclotetrasiloxane, 3.12 grams of dodecylbenzenesulfonic acidand 208 grams water. Additional water (60 grams) was added and thereaction mixture was maintained at 85° C. for an additional 90 minutes,then cooled to room temperature. An aminosilicone fluid SF1708 (4.2grams) was thereafter added to the reaction mixture with stirring. Theresulting reaction mixture was heated at 85° C. for 300 minutes andcooled to room temperature. Based on method of preparation andanalytical procedures shown in Example 1, there was obtained an aqueousemulsion of amine functionalized organopolysiloxane particles having avolume average particle diameter of 311 nanometers and a total weight %solids of 40.8%. The aqueous emulsion of amine functionalizedorganopolysiloxane particles is useful in personal care applications.

[0034] Although the above examples are directed to only a few of thevery many variables to which the present invention is directed, itshould be understood that the present invention is directed to a muchbroader variety of substantially stable aqueous emulsions of aminefunctionalized organopolysiloxane particles having a volume averageparticle diameter in a range between about 300 nanometers and about 1micron, and methods for making such materials.

What is claimed:
 1. An aqueous emulsion of amine functionalizedorganopolysiloxane particles having a volume average particle diameterof at least about 300 nanometers.
 2. The aqueous emulsion in accordancewith claim 1 , wherein the aqueous emulsion consists essentially ofchemically combined dimethylsiloxy units and (aminopropyl)methylsiloxyunits.
 3. The aqueous emulsion in accordance with claim 1 , which isuseful in personal care applications.
 4. A substantially stable aqueousemulsion having solids in a range between about 5% by weight and about60% by weight, comprising amine functionalized organopolysiloxaneparticles having a volume average particle diameter of at least about300 nanometers, said particles consisting essentially of diorganosiloxyunits in a range between about 50 mole % and about 99 mole % chemicallycombined with (aminoorgano)organosiloxy units in a range between about50 mole % and about 1 mole %.
 5. The substantially stable aqueousemulsion in accordance with claim 4 , wherein the amine functionalizedorganopolysiloxane particles are derived from the reaction between anaqueous emulsion of organopolysiloxane particles and an aminefunctionalized poly(diorganosiloxane) fluid.
 6. The substantially stableaqueous emulsion in accordance with claim 4 , wherein the aminefunctionalized organopolysiloxane particles are derived from thereaction between organopolysiloxane particles and anaminoorganopolyalkoxysilane.
 7. The substantially stable aqueousemulsion in accordance with claim 6 , wherein theaminoorganopolyalkoxysilane comprises gamma-aminopropyltriethoxysilane.8. The substantially stable aqueous emulsion in accordance with claim 4, which is useful in personal care applications.
 9. A method for makingan aqueous emulsion of amine functionalized organopolysiloxane particleshaving a total solids content in a range between about 5% by weight andabout 60% by weight, comprising effecting reaction at a temperature in arange between about 25° C. and about 110° C., and in the presence of aneffective amount of an acid catalyst surfactant, between (A) an aqueousemulsion of organopolysiloxane particles having a volume averageparticle diameter of at least about 300 nanometers, and (B) an aminefunctionalized organosilicon source material, wherein there is used byweight in a range between about 1 part and about 50 parts by weight of(B) per 100 parts of (A).
 10. The method in accordance with claim 9 ,wherein the organopolysiloxane particles comprise poly(diorganosiloxane)structural units.
 11. The method in accordance with claim 9 , whereinthe amine functionalized organosilicon source material comprises anamine functionalized poly(diorganosiloxane) fluid.
 12. The method inaccordance with claim 9 , wherein the amine functionalized organosiliconsource material comprises an aminoorganopolyalkoxysilane.
 13. The methodin accordance with claim 12 , wherein the aminoorganopolyalkoxysilanecomprises gamma-aminopropyltriethoxysilane.
 14. The method in accordancewith claim 9 , wherein the acid catalyst surfactant comprisesdodecylbenzenesulfonic acid.
 15. The method in accordance with claim 9 ,wherein the aqueous emulsion is useful in personal care applications.16. A method for making an aqueous emulsion of amine functionalizedorganopolysiloxane particles having a total solids content in a rangebetween about 30% by weight and about 60% by weight, comprisingeffecting contact at a temperature in a range between about roomtemperature and about 90° C., and in the presence of an effective amountof an acid catalyst surfactant, between (A) an aqueous emulsion oforganopolysiloxane particles having a volume average particle diameterin a range between about 300 nanometers and about 1 micron, and (B)either an amine functionalized poly(diorganosiloxane) fluid or anaminoorganopolyalkoxysilane, wherein there is used in a range betweenabout 1 part and about 10 parts by weight of (B) per 100 parts of (A).17. The method in accordance with claim 16 , wherein the aqueousemulsion is useful in personal care applications.
 18. A method formaking a substantially stable aqueous emulsion having solids in a rangebetween about 5% by weight and about 60% by weight, and comprising aminefunctionalized organopolysiloxane particles having a volume averageparticle diameter of at least about 300 nanometers, comprising the stepsof: (1) providing an aqueous emulsion comprising in a range betweenabout 1% by weight and about 50% by weight organopolysiloxane particleshaving a volume average particle diameter of at least about 300nanometers, by either, (a) equilibrating under semi-continuousconditions at a temperature in a range between about 25° C. and about110° C. an aqueous mixture comprising cyclic poly(diorganosiloxane) andan effective amount of an acid catalyst surfactant to form an aqueousemulsion of organopolysiloxane particles having a volume averageparticle diameter of at least about 300 nanometers, or (b) employing anaqueous emulsion of preformed organopolysiloxane emulsion seeds having avolume average particle diameter of at least about 300 nanometers; and(2) effecting reaction between the organopolysiloxane particles or seedsin the aqueous emulsion of (1), and an amine functionalizedorganosilicon source material in a range between about 1 part and about50 parts by weight of per 100 parts of such organopolysiloxane particlesor seeds.
 19. The method in accordance with claim 18 , wherein thecyclic poly(diorganosiloxane) comprises octamethylcyclotetrasiloxane.20. A method for making a substantially stable aqueous emulsion havingsolids in a range between about 30% by weight and about 60% by weight,and comprising amine functionalized organopolysiloxane particles havinga volume average particle diameter of at least about 300 nanometers,comprising the steps of: (1) providing an aqueous emulsion comprisingorganopolysiloxane particles in a range between about 1% and about 50%by weight having a volume average particle diameter in a range betweenabout 300 nanometers and about 1 micron, by either, (a) equilibratingunder semi-continuous conditions at a temperature in a range betweenabout 25° C. and about 110° C. an aqueous mixture comprisingoctamethylcyclotetrasiloxane and an effective amount of an acid catalystsurfactant to form an aqueous emulsion of organopolysiloxane particleshaving a volume average particle diameter of at least about 300nanometers, or (b) employing an aqueous emulsion of preformedorganopolysiloxane emulsion seeds having a volume average particlediameter in a range between about 300 nanometers and about 1 micron; and(2) effecting reaction between the organopolysiloxane particles or seedsin the aqueous emulsion of (1), and either an amine functionalizedpoly(diorganosiloxane) fluid or an aminoorganopolyalkoxysilane in arange between about 1 part and about 50 parts by weight of per 100 partsof such organopolysiloxane particles or seeds.